1. FIELD OF THE INVENTION
This invention relates generally to amplifier circuits, and more particularly to an output stage for an amplifier having capacitive loading.
2. PRIOR ART
A typical class A-B output stage under capacitive loading employs an NPN transistor for sourcing a current to the load and a PNP transistor for sinking current from the load. Generally, PNP transistors produce a relatively large phase shift when sinking current from the load. These large phase shifts limit the overall loop stability and bandwidth of the amplifier.
Accordingly, it can be appreciated that a need exists for an amplifier output stage which is capable of sinking current from a capacitive load without producing a relatively large phase shift.